RXBARs are one of the most popular nutrition bars on the market right now. They’re simple, healthy and packaged in an aesthetically pleasing way. They’re the pinnacle of millennial diet demands, a reflection of Instagram trends and a product of Chicago’s growing food startup scene.

Since news broke that the maker of RXBAR, the Chicago Bar Company, is being acquired by breakfast and snack food conglomerate Kellogg for $600 million, RXBAR has joined the ranks of Chicago’s most notable food startup success stories. It’s up there with Skinnypop and GrubHub, companies that have helped establish the city as a place where food innovation can thrive.

Peter Rahal made his first RXBAR in 2013 in his parent’s basement out in the Chicago suburbs with his co-founder Jared Smith. RXBARs were made with simplicity in mind. They only contain four main ingredients: egg whites, almonds, cashews and dates.

Now Rahal employs 75 people in RXBAR’s River North offices and sells 15 different flavors of the nutrition bar.

With a huge exit and anticipated revenue this year topping $120 million, you’d think Rahal would be celebrating. But he says he’s not popping the champagne just yet.

“It’s not really an exit. There’s no exodus,” he said. “There’s more work to be done.”

Rahal, who worked in Chicago tech before launching RXBAR, said he wanted to make his own nutrition bar because he was sick of all the added and artificial ingredients in ones that were available.

“Why are all the protein bars full of shit?” he asked.

It turns out he wasn’t the only one wondering. When RXBARs hit the market, they were appealing to a growing number of consumers who were interested in eating more health-conscious foods.

“That’s the wave we’ve been riding,” Rahal said.

Another wave that helped boost RXBARs profile was the rise of influencer marketing on Instagram in 2013 when Rahal was making the first RXBARs. Rahal said the social media platform has been one of the most useful marketing tools available to them, and it shows.

RXBAR has taken the time to craft a compelling and aesthetically pleasing Instagram profile, hyping up new flavors and showing viewers where they can buy them. With compelling and engaging photography, they’ve managed to gather more than 211,000 followers.

But it hasn’t always been smooth sailing for the company, Rahal said. Whether it was struggling to commercialize the bars or striving to attract and retain talented employees, RXBAR ran into common entrepreneurial problems along the way. But despite those challenges, building RXBAR in Chicago gave Rahal advantages that he couldn’t have gotten elsewhere. Launching a company in the Midwest gives companies greater access to markets on the coasts, making it an ideal area to sell in from a distribution standpoint, he said.

Additionally, building a company in Chicago specifically gives business owners bigger and better pools of talent to choose from when hiring. Not only does the city produce prospective employees every year from the several colleges within the Chicagoland area, but many students from colleges in nearby states move to the city after graduation.

“I couldn’t imagine not having access to great talent,” Rahal said. “All that matters is people. That’s the only way to grow the business.”

And Rahal plans to continue growing his workforce at the company, noting that he expects his team of 75 to grow to about 150 within the next year. They have 45 open positions now across all departments, including marketing, sales and accounting.

If Rahal gets his way, RXBAR will only continue to grow and maybe, eventually, dominate the protein and nutrition bar market. There have been milestones to celebrate along the way and Rahal hopes there’s even more to look forward to. But even in the midst of his current and future successes, he doesn’t want to spend too much time reveling in them.

“You look forward to those milestones because you think it’s going to slow down,” he said. “But then you realize that as the business grows, it doesn’t ever really slow down. It actually speeds up. I’m busy as fuck.”